Article Text
Abstract
Objectives Pulmonary veno-occlusive disease (PVOD) is a rare type of pulmonary hypertension, with similar clinical presentation to pulmonary arterial hypertension (PAH) but poorer prognosis and higher possibility to develop sever pulmonary oedema after specific PAH therapy, which have manifest the significance to distinguish PVOD from PAH for proper diagnose and clinical management.
Methods We reported a 40-year-old male patient with a history of progressive dyspnea, fatigue, try cough, with a diagnosis of PAH confirmed elsewhere, was ultimately diagnosed as PVOD via non-invasive approaches—pulmonary function test (PFT), high-resolution CT scan of chest and bronchoalveolar lavage. In this paper, we also reviewed some published literature and discussed the differences between PVOD and PAH in all kinds of clinical aspects and highlighted the cautious application of PAH specific therapy strategy.
Results The arterial blood gas analysis revealed severe hypoxemia (pH 7.47, PaCO2 30mm Hg, PaO2 53 mmHg and SO2 89% in room air). The pulmonary function testing identified no restrictive ventilatory defects (FEV1/FVC was 79.55%, VC 61.9% of predicted value) but a marked reduction in CO diffusion (DLCO was 35.8% of predicted value). The plasma level of N-terminal pro-brain natriuretic peptide (NT-proBNP) was 3180 pg/mL. The transthoracic echocardiography showed an enlarged right ventricle and atrium, moderate tricuspid regurgitation, bilateral pulmonary artery dilated and a small pericardial effusion. High-resolution computed tomography (HRCT) scan of the chest revealed interstitial oedema, enlarged lymph nodes in the mediastinum, few inflammation lesions on the superior lobe of left lung and the both main bronchi were compressed by the dilated pulmonary artery. CT pulmonary angiography showed dilated pulmonary arteries without embolism. The right heart catherization revealed mean pulmonary artery pressure as 57 mm Hg, and mean pulmonary capillary wedge pressure 14 mm Hg, showed as the pre-capillary pulmonary hypertension. The bronchoalveolar lavage confirmed occult alveolar haemorrhage by detecting hemosiderin-laden macrophages. Considering the risk of pulmonary oedema, the patient declined the specific PAH therapy. After treatment with warfarin (kept INR 2.0–3.0), diuretics, digtoxin and oxygen therapy, his symptoms improved in 3 months follow-up while ultimately died of right heart failure 18 months later.
Conclusions This case justifies that PVOD should be taken into consideration when a PAH patient demonstrate remarkably low diffusing capacity of the lung for carbon monoxide (DLCO). The lung biopsy is the gold diagnostic standard, but usually not feasible. High-resolution CT scan and bronchoalveolar lavage are valuable for non-invasive approaches of PVOD which reveal the interstitial edema of the lungs and occult alveolar hemorrhage respectively in the patients with diagnosis of PAH and low diffusing capacity of the lung. Lung transplantation remains a feasible option of treatment. The specific therapies for PAH is cautiously recommended with extra attention to the possibility of developing pulmonary edema. Anticoagulation, diuretics and oxygen therapy merit evaluation.